Right now, the one missing feature that is completely preventing me from pursuing PWA more aggressively is the inability to know if the user has already installed. Is this something you’re keeping track of in your own server-side storage? User clicks to install and you store OAuth id and installed:true on your side? Are you using localStorage and assuming that 0% of your user base employs more than one mobile browser? Are you ignoring the problem and prompting users to install even if they already have?